We are working on a campus project that contains multiple NC and F&B CS buildings. We'll be registering the master site and the individual buildings under the campus approach. A centralized plant system (5 air cooled chillers connected to a CHW network) that is located on the roof of one of the buildings will be serving all buildings within the master site boundary. This even includes existing buildings that will not be targeting LEED certification within the master site.

Our understanding, based on the LEED V4 guidelines, is that each individual building will need to consider the plant system (upstream equipment) as a Campus Thermal Energy System (DC System) in the energy model. Is this correct?

If applying the campus thermal energy approach is correct, we would prefer to opt for path 2 (Full DES Performance accounting) instead of path 1 (purchased cooling); however we not have the the average SCOP of the air-cooled chiller system. The handbook states that default assumptions for COP and distribution losses can be used if average COP values are missing; however it does state that they "prefer" to see actual average COP values instead. Would it be permissable to use the default assumptions for the upstream equipment even if it is located within our site boundary, and we have information about the full load COP of the air cooled chiller equipment? 

We appreciate your comments.